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Phase diagram and symmetry breaking of SU(4) spin-orbital chain in a generalized external field

Shi-Jian Gu·You-Quan Li·Huan-Qiang Zhou
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Abstract

The ground state phases of a one-dimensional SU(4) spin-orbital Hamiltonian in a generalized external field are studied on the basis of Bethe-ansatz solution. Introducing three Landé $g$ factors for spin, orbital and their products in the SU(4) Zeeman term, we discuss systematically the various symmetry breaking. The magnetization versus external field are obtained by solving Bethe-ansatz equations numerically. The phase diagrams corresponding to distinct residual symmetries are given by means of both numerical and analytical methods.

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Shi-Jian Gu, You-Quan Li, Huan-Qiang Zhou. 2003-08-21. Phase diagram and symmetry breaking of SU(4) spin-orbital chain in a generalized external field. https://doi.org/10.1103/physrevb.69.144405

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